1 78 ^Journal of Comparative Neurology and Psychology. 



It is believed that such names are more in accord with embryo- 

 logical knowledge than those of the German society in 18955 

 whereby the motor portion of the trigeminus was named, as above, 

 the portio minor; the motor part of the glossopharyngeus received 

 no name; but the corresponding parts of the intermedins and 



Fig. I. Diagrams of the trigeminus, Tr/.; the intermedius, 7«r.; the glossophar}'ngeus, Glos.; 

 and the vagus nerves, showing their sensory portions shaded, and their motor portions in soHd black. 

 The somatic sensory branches have been omitted. The numbers indicate the gill clefts counting the 

 spiracle as the first; 5, in B, marks the postbranchial body. A, a generalized diagram based chiefly 

 upon Petromyzon, after Johnston. B,a diagram following closely the conditions in a pig embryo 

 of 12 mm. 



vagus w^ere counted as separate nerves, the facial and the acces- 

 sory. The change proposed is, however, so easily understood as 

 scarcely to require explanation. It is a slight change, but by its 

 adoption attention is drawn to the fundamental morphological 

 similarity between these four mixed nerves. 



The branches of these nerves can best be understood by con- 

 sidering them first in the low^er vertebrates. They are shown in 



